2 V4L2 controls framework implementation.
4 Copyright (C) 2010 Hans Verkuil <hverkuil@xs4all.nl>
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 #include <linux/ctype.h>
22 #include <linux/slab.h>
23 #include <media/v4l2-ioctl.h>
24 #include <media/v4l2-device.h>
25 #include <media/v4l2-ctrls.h>
26 #include <media/v4l2-event.h>
27 #include <media/v4l2-dev.h>
29 #define has_op(master, op) \
30 (master->ops && master->ops->op)
31 #define call_op(master, op) \
32 (has_op(master, op) ? master->ops->op(master) : 0)
34 /* Internal temporary helper struct, one for each v4l2_ext_control */
35 struct v4l2_ctrl_helper {
36 /* Pointer to the control reference of the master control */
37 struct v4l2_ctrl_ref *mref;
38 /* The control corresponding to the v4l2_ext_control ID field. */
39 struct v4l2_ctrl *ctrl;
40 /* v4l2_ext_control index of the next control belonging to the
41 same cluster, or 0 if there isn't any. */
45 /* Small helper function to determine if the autocluster is set to manual
46 mode. In that case the is_volatile flag should be ignored. */
47 static bool is_cur_manual(const struct v4l2_ctrl *master)
49 return master->is_auto && master->cur.val == master->manual_mode_value;
52 /* Same as above, but this checks the against the new value instead of the
54 static bool is_new_manual(const struct v4l2_ctrl *master)
56 return master->is_auto && master->val == master->manual_mode_value;
59 /* Returns NULL or a character pointer array containing the menu for
60 the given control ID. The pointer array ends with a NULL pointer.
61 An empty string signifies a menu entry that is invalid. This allows
62 drivers to disable certain options if it is not supported. */
63 const char * const *v4l2_ctrl_get_menu(u32 id)
65 static const char * const mpeg_audio_sampling_freq[] = {
71 static const char * const mpeg_audio_encoding[] = {
79 static const char * const mpeg_audio_l1_bitrate[] = {
96 static const char * const mpeg_audio_l2_bitrate[] = {
113 static const char * const mpeg_audio_l3_bitrate[] = {
130 static const char * const mpeg_audio_ac3_bitrate[] = {
152 static const char * const mpeg_audio_mode[] = {
159 static const char * const mpeg_audio_mode_extension[] = {
166 static const char * const mpeg_audio_emphasis[] = {
172 static const char * const mpeg_audio_crc[] = {
177 static const char * const mpeg_video_encoding[] = {
183 static const char * const mpeg_video_aspect[] = {
190 static const char * const mpeg_video_bitrate_mode[] = {
195 static const char * const mpeg_stream_type[] = {
196 "MPEG-2 Program Stream",
197 "MPEG-2 Transport Stream",
198 "MPEG-1 System Stream",
199 "MPEG-2 DVD-compatible Stream",
200 "MPEG-1 VCD-compatible Stream",
201 "MPEG-2 SVCD-compatible Stream",
204 static const char * const mpeg_stream_vbi_fmt[] = {
206 "Private packet, IVTV format",
209 static const char * const camera_power_line_frequency[] = {
215 static const char * const camera_exposure_auto[] = {
218 "Shutter Priority Mode",
219 "Aperture Priority Mode",
222 static const char * const colorfx[] = {
235 static const char * const tune_preemphasis[] = {
243 case V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ:
244 return mpeg_audio_sampling_freq;
245 case V4L2_CID_MPEG_AUDIO_ENCODING:
246 return mpeg_audio_encoding;
247 case V4L2_CID_MPEG_AUDIO_L1_BITRATE:
248 return mpeg_audio_l1_bitrate;
249 case V4L2_CID_MPEG_AUDIO_L2_BITRATE:
250 return mpeg_audio_l2_bitrate;
251 case V4L2_CID_MPEG_AUDIO_L3_BITRATE:
252 return mpeg_audio_l3_bitrate;
253 case V4L2_CID_MPEG_AUDIO_AC3_BITRATE:
254 return mpeg_audio_ac3_bitrate;
255 case V4L2_CID_MPEG_AUDIO_MODE:
256 return mpeg_audio_mode;
257 case V4L2_CID_MPEG_AUDIO_MODE_EXTENSION:
258 return mpeg_audio_mode_extension;
259 case V4L2_CID_MPEG_AUDIO_EMPHASIS:
260 return mpeg_audio_emphasis;
261 case V4L2_CID_MPEG_AUDIO_CRC:
262 return mpeg_audio_crc;
263 case V4L2_CID_MPEG_VIDEO_ENCODING:
264 return mpeg_video_encoding;
265 case V4L2_CID_MPEG_VIDEO_ASPECT:
266 return mpeg_video_aspect;
267 case V4L2_CID_MPEG_VIDEO_BITRATE_MODE:
268 return mpeg_video_bitrate_mode;
269 case V4L2_CID_MPEG_STREAM_TYPE:
270 return mpeg_stream_type;
271 case V4L2_CID_MPEG_STREAM_VBI_FMT:
272 return mpeg_stream_vbi_fmt;
273 case V4L2_CID_POWER_LINE_FREQUENCY:
274 return camera_power_line_frequency;
275 case V4L2_CID_EXPOSURE_AUTO:
276 return camera_exposure_auto;
277 case V4L2_CID_COLORFX:
279 case V4L2_CID_TUNE_PREEMPHASIS:
280 return tune_preemphasis;
285 EXPORT_SYMBOL(v4l2_ctrl_get_menu);
287 /* Return the control name. */
288 const char *v4l2_ctrl_get_name(u32 id)
292 /* Keep the order of the 'case's the same as in videodev2.h! */
293 case V4L2_CID_USER_CLASS: return "User Controls";
294 case V4L2_CID_BRIGHTNESS: return "Brightness";
295 case V4L2_CID_CONTRAST: return "Contrast";
296 case V4L2_CID_SATURATION: return "Saturation";
297 case V4L2_CID_HUE: return "Hue";
298 case V4L2_CID_AUDIO_VOLUME: return "Volume";
299 case V4L2_CID_AUDIO_BALANCE: return "Balance";
300 case V4L2_CID_AUDIO_BASS: return "Bass";
301 case V4L2_CID_AUDIO_TREBLE: return "Treble";
302 case V4L2_CID_AUDIO_MUTE: return "Mute";
303 case V4L2_CID_AUDIO_LOUDNESS: return "Loudness";
304 case V4L2_CID_BLACK_LEVEL: return "Black Level";
305 case V4L2_CID_AUTO_WHITE_BALANCE: return "White Balance, Automatic";
306 case V4L2_CID_DO_WHITE_BALANCE: return "Do White Balance";
307 case V4L2_CID_RED_BALANCE: return "Red Balance";
308 case V4L2_CID_BLUE_BALANCE: return "Blue Balance";
309 case V4L2_CID_GAMMA: return "Gamma";
310 case V4L2_CID_EXPOSURE: return "Exposure";
311 case V4L2_CID_AUTOGAIN: return "Gain, Automatic";
312 case V4L2_CID_GAIN: return "Gain";
313 case V4L2_CID_HFLIP: return "Horizontal Flip";
314 case V4L2_CID_VFLIP: return "Vertical Flip";
315 case V4L2_CID_HCENTER: return "Horizontal Center";
316 case V4L2_CID_VCENTER: return "Vertical Center";
317 case V4L2_CID_POWER_LINE_FREQUENCY: return "Power Line Frequency";
318 case V4L2_CID_HUE_AUTO: return "Hue, Automatic";
319 case V4L2_CID_WHITE_BALANCE_TEMPERATURE: return "White Balance Temperature";
320 case V4L2_CID_SHARPNESS: return "Sharpness";
321 case V4L2_CID_BACKLIGHT_COMPENSATION: return "Backlight Compensation";
322 case V4L2_CID_CHROMA_AGC: return "Chroma AGC";
323 case V4L2_CID_COLOR_KILLER: return "Color Killer";
324 case V4L2_CID_COLORFX: return "Color Effects";
325 case V4L2_CID_AUTOBRIGHTNESS: return "Brightness, Automatic";
326 case V4L2_CID_BAND_STOP_FILTER: return "Band-Stop Filter";
327 case V4L2_CID_ROTATE: return "Rotate";
328 case V4L2_CID_BG_COLOR: return "Background Color";
329 case V4L2_CID_CHROMA_GAIN: return "Chroma Gain";
330 case V4L2_CID_ILLUMINATORS_1: return "Illuminator 1";
331 case V4L2_CID_ILLUMINATORS_2: return "Illuminator 2";
334 /* Keep the order of the 'case's the same as in videodev2.h! */
335 case V4L2_CID_MPEG_CLASS: return "MPEG Encoder Controls";
336 case V4L2_CID_MPEG_STREAM_TYPE: return "Stream Type";
337 case V4L2_CID_MPEG_STREAM_PID_PMT: return "Stream PMT Program ID";
338 case V4L2_CID_MPEG_STREAM_PID_AUDIO: return "Stream Audio Program ID";
339 case V4L2_CID_MPEG_STREAM_PID_VIDEO: return "Stream Video Program ID";
340 case V4L2_CID_MPEG_STREAM_PID_PCR: return "Stream PCR Program ID";
341 case V4L2_CID_MPEG_STREAM_PES_ID_AUDIO: return "Stream PES Audio ID";
342 case V4L2_CID_MPEG_STREAM_PES_ID_VIDEO: return "Stream PES Video ID";
343 case V4L2_CID_MPEG_STREAM_VBI_FMT: return "Stream VBI Format";
344 case V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ: return "Audio Sampling Frequency";
345 case V4L2_CID_MPEG_AUDIO_ENCODING: return "Audio Encoding";
346 case V4L2_CID_MPEG_AUDIO_L1_BITRATE: return "Audio Layer I Bitrate";
347 case V4L2_CID_MPEG_AUDIO_L2_BITRATE: return "Audio Layer II Bitrate";
348 case V4L2_CID_MPEG_AUDIO_L3_BITRATE: return "Audio Layer III Bitrate";
349 case V4L2_CID_MPEG_AUDIO_MODE: return "Audio Stereo Mode";
350 case V4L2_CID_MPEG_AUDIO_MODE_EXTENSION: return "Audio Stereo Mode Extension";
351 case V4L2_CID_MPEG_AUDIO_EMPHASIS: return "Audio Emphasis";
352 case V4L2_CID_MPEG_AUDIO_CRC: return "Audio CRC";
353 case V4L2_CID_MPEG_AUDIO_MUTE: return "Audio Mute";
354 case V4L2_CID_MPEG_AUDIO_AAC_BITRATE: return "Audio AAC Bitrate";
355 case V4L2_CID_MPEG_AUDIO_AC3_BITRATE: return "Audio AC-3 Bitrate";
356 case V4L2_CID_MPEG_VIDEO_ENCODING: return "Video Encoding";
357 case V4L2_CID_MPEG_VIDEO_ASPECT: return "Video Aspect";
358 case V4L2_CID_MPEG_VIDEO_B_FRAMES: return "Video B Frames";
359 case V4L2_CID_MPEG_VIDEO_GOP_SIZE: return "Video GOP Size";
360 case V4L2_CID_MPEG_VIDEO_GOP_CLOSURE: return "Video GOP Closure";
361 case V4L2_CID_MPEG_VIDEO_PULLDOWN: return "Video Pulldown";
362 case V4L2_CID_MPEG_VIDEO_BITRATE_MODE: return "Video Bitrate Mode";
363 case V4L2_CID_MPEG_VIDEO_BITRATE: return "Video Bitrate";
364 case V4L2_CID_MPEG_VIDEO_BITRATE_PEAK: return "Video Peak Bitrate";
365 case V4L2_CID_MPEG_VIDEO_TEMPORAL_DECIMATION: return "Video Temporal Decimation";
366 case V4L2_CID_MPEG_VIDEO_MUTE: return "Video Mute";
367 case V4L2_CID_MPEG_VIDEO_MUTE_YUV: return "Video Mute YUV";
369 /* CAMERA controls */
370 /* Keep the order of the 'case's the same as in videodev2.h! */
371 case V4L2_CID_CAMERA_CLASS: return "Camera Controls";
372 case V4L2_CID_EXPOSURE_AUTO: return "Auto Exposure";
373 case V4L2_CID_EXPOSURE_ABSOLUTE: return "Exposure Time, Absolute";
374 case V4L2_CID_EXPOSURE_AUTO_PRIORITY: return "Exposure, Dynamic Framerate";
375 case V4L2_CID_PAN_RELATIVE: return "Pan, Relative";
376 case V4L2_CID_TILT_RELATIVE: return "Tilt, Relative";
377 case V4L2_CID_PAN_RESET: return "Pan, Reset";
378 case V4L2_CID_TILT_RESET: return "Tilt, Reset";
379 case V4L2_CID_PAN_ABSOLUTE: return "Pan, Absolute";
380 case V4L2_CID_TILT_ABSOLUTE: return "Tilt, Absolute";
381 case V4L2_CID_FOCUS_ABSOLUTE: return "Focus, Absolute";
382 case V4L2_CID_FOCUS_RELATIVE: return "Focus, Relative";
383 case V4L2_CID_FOCUS_AUTO: return "Focus, Automatic";
384 case V4L2_CID_ZOOM_ABSOLUTE: return "Zoom, Absolute";
385 case V4L2_CID_ZOOM_RELATIVE: return "Zoom, Relative";
386 case V4L2_CID_ZOOM_CONTINUOUS: return "Zoom, Continuous";
387 case V4L2_CID_PRIVACY: return "Privacy";
388 case V4L2_CID_IRIS_ABSOLUTE: return "Iris, Absolute";
389 case V4L2_CID_IRIS_RELATIVE: return "Iris, Relative";
391 /* FM Radio Modulator control */
392 /* Keep the order of the 'case's the same as in videodev2.h! */
393 case V4L2_CID_FM_TX_CLASS: return "FM Radio Modulator Controls";
394 case V4L2_CID_RDS_TX_DEVIATION: return "RDS Signal Deviation";
395 case V4L2_CID_RDS_TX_PI: return "RDS Program ID";
396 case V4L2_CID_RDS_TX_PTY: return "RDS Program Type";
397 case V4L2_CID_RDS_TX_PS_NAME: return "RDS PS Name";
398 case V4L2_CID_RDS_TX_RADIO_TEXT: return "RDS Radio Text";
399 case V4L2_CID_AUDIO_LIMITER_ENABLED: return "Audio Limiter Feature Enabled";
400 case V4L2_CID_AUDIO_LIMITER_RELEASE_TIME: return "Audio Limiter Release Time";
401 case V4L2_CID_AUDIO_LIMITER_DEVIATION: return "Audio Limiter Deviation";
402 case V4L2_CID_AUDIO_COMPRESSION_ENABLED: return "Audio Compression Feature Enabled";
403 case V4L2_CID_AUDIO_COMPRESSION_GAIN: return "Audio Compression Gain";
404 case V4L2_CID_AUDIO_COMPRESSION_THRESHOLD: return "Audio Compression Threshold";
405 case V4L2_CID_AUDIO_COMPRESSION_ATTACK_TIME: return "Audio Compression Attack Time";
406 case V4L2_CID_AUDIO_COMPRESSION_RELEASE_TIME: return "Audio Compression Release Time";
407 case V4L2_CID_PILOT_TONE_ENABLED: return "Pilot Tone Feature Enabled";
408 case V4L2_CID_PILOT_TONE_DEVIATION: return "Pilot Tone Deviation";
409 case V4L2_CID_PILOT_TONE_FREQUENCY: return "Pilot Tone Frequency";
410 case V4L2_CID_TUNE_PREEMPHASIS: return "Pre-emphasis settings";
411 case V4L2_CID_TUNE_POWER_LEVEL: return "Tune Power Level";
412 case V4L2_CID_TUNE_ANTENNA_CAPACITOR: return "Tune Antenna Capacitor";
418 EXPORT_SYMBOL(v4l2_ctrl_get_name);
420 void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
421 s32 *min, s32 *max, s32 *step, s32 *def, u32 *flags)
423 *name = v4l2_ctrl_get_name(id);
427 case V4L2_CID_AUDIO_MUTE:
428 case V4L2_CID_AUDIO_LOUDNESS:
429 case V4L2_CID_AUTO_WHITE_BALANCE:
430 case V4L2_CID_AUTOGAIN:
433 case V4L2_CID_HUE_AUTO:
434 case V4L2_CID_CHROMA_AGC:
435 case V4L2_CID_COLOR_KILLER:
436 case V4L2_CID_MPEG_AUDIO_MUTE:
437 case V4L2_CID_MPEG_VIDEO_MUTE:
438 case V4L2_CID_MPEG_VIDEO_GOP_CLOSURE:
439 case V4L2_CID_MPEG_VIDEO_PULLDOWN:
440 case V4L2_CID_EXPOSURE_AUTO_PRIORITY:
441 case V4L2_CID_FOCUS_AUTO:
442 case V4L2_CID_PRIVACY:
443 case V4L2_CID_AUDIO_LIMITER_ENABLED:
444 case V4L2_CID_AUDIO_COMPRESSION_ENABLED:
445 case V4L2_CID_PILOT_TONE_ENABLED:
446 case V4L2_CID_ILLUMINATORS_1:
447 case V4L2_CID_ILLUMINATORS_2:
448 *type = V4L2_CTRL_TYPE_BOOLEAN;
452 case V4L2_CID_PAN_RESET:
453 case V4L2_CID_TILT_RESET:
454 *type = V4L2_CTRL_TYPE_BUTTON;
455 *flags |= V4L2_CTRL_FLAG_WRITE_ONLY;
456 *min = *max = *step = *def = 0;
458 case V4L2_CID_POWER_LINE_FREQUENCY:
459 case V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ:
460 case V4L2_CID_MPEG_AUDIO_ENCODING:
461 case V4L2_CID_MPEG_AUDIO_L1_BITRATE:
462 case V4L2_CID_MPEG_AUDIO_L2_BITRATE:
463 case V4L2_CID_MPEG_AUDIO_L3_BITRATE:
464 case V4L2_CID_MPEG_AUDIO_AC3_BITRATE:
465 case V4L2_CID_MPEG_AUDIO_MODE:
466 case V4L2_CID_MPEG_AUDIO_MODE_EXTENSION:
467 case V4L2_CID_MPEG_AUDIO_EMPHASIS:
468 case V4L2_CID_MPEG_AUDIO_CRC:
469 case V4L2_CID_MPEG_VIDEO_ENCODING:
470 case V4L2_CID_MPEG_VIDEO_ASPECT:
471 case V4L2_CID_MPEG_VIDEO_BITRATE_MODE:
472 case V4L2_CID_MPEG_STREAM_TYPE:
473 case V4L2_CID_MPEG_STREAM_VBI_FMT:
474 case V4L2_CID_EXPOSURE_AUTO:
475 case V4L2_CID_COLORFX:
476 case V4L2_CID_TUNE_PREEMPHASIS:
477 *type = V4L2_CTRL_TYPE_MENU;
479 case V4L2_CID_RDS_TX_PS_NAME:
480 case V4L2_CID_RDS_TX_RADIO_TEXT:
481 *type = V4L2_CTRL_TYPE_STRING;
483 case V4L2_CID_USER_CLASS:
484 case V4L2_CID_CAMERA_CLASS:
485 case V4L2_CID_MPEG_CLASS:
486 case V4L2_CID_FM_TX_CLASS:
487 *type = V4L2_CTRL_TYPE_CTRL_CLASS;
488 /* You can neither read not write these */
489 *flags |= V4L2_CTRL_FLAG_READ_ONLY | V4L2_CTRL_FLAG_WRITE_ONLY;
490 *min = *max = *step = *def = 0;
492 case V4L2_CID_BG_COLOR:
493 *type = V4L2_CTRL_TYPE_INTEGER;
496 /* Max is calculated as RGB888 that is 2^24 */
500 *type = V4L2_CTRL_TYPE_INTEGER;
504 case V4L2_CID_MPEG_AUDIO_ENCODING:
505 case V4L2_CID_MPEG_AUDIO_MODE:
506 case V4L2_CID_MPEG_VIDEO_BITRATE_MODE:
507 case V4L2_CID_MPEG_VIDEO_B_FRAMES:
508 case V4L2_CID_MPEG_STREAM_TYPE:
509 *flags |= V4L2_CTRL_FLAG_UPDATE;
511 case V4L2_CID_AUDIO_VOLUME:
512 case V4L2_CID_AUDIO_BALANCE:
513 case V4L2_CID_AUDIO_BASS:
514 case V4L2_CID_AUDIO_TREBLE:
515 case V4L2_CID_BRIGHTNESS:
516 case V4L2_CID_CONTRAST:
517 case V4L2_CID_SATURATION:
519 case V4L2_CID_RED_BALANCE:
520 case V4L2_CID_BLUE_BALANCE:
522 case V4L2_CID_SHARPNESS:
523 case V4L2_CID_CHROMA_GAIN:
524 case V4L2_CID_RDS_TX_DEVIATION:
525 case V4L2_CID_AUDIO_LIMITER_RELEASE_TIME:
526 case V4L2_CID_AUDIO_LIMITER_DEVIATION:
527 case V4L2_CID_AUDIO_COMPRESSION_GAIN:
528 case V4L2_CID_AUDIO_COMPRESSION_THRESHOLD:
529 case V4L2_CID_AUDIO_COMPRESSION_ATTACK_TIME:
530 case V4L2_CID_AUDIO_COMPRESSION_RELEASE_TIME:
531 case V4L2_CID_PILOT_TONE_DEVIATION:
532 case V4L2_CID_PILOT_TONE_FREQUENCY:
533 case V4L2_CID_TUNE_POWER_LEVEL:
534 case V4L2_CID_TUNE_ANTENNA_CAPACITOR:
535 *flags |= V4L2_CTRL_FLAG_SLIDER;
537 case V4L2_CID_PAN_RELATIVE:
538 case V4L2_CID_TILT_RELATIVE:
539 case V4L2_CID_FOCUS_RELATIVE:
540 case V4L2_CID_IRIS_RELATIVE:
541 case V4L2_CID_ZOOM_RELATIVE:
542 *flags |= V4L2_CTRL_FLAG_WRITE_ONLY;
546 EXPORT_SYMBOL(v4l2_ctrl_fill);
548 /* Helper function to determine whether the control type is compatible with
550 static bool type_is_int(const struct v4l2_ctrl *ctrl)
552 switch (ctrl->type) {
553 case V4L2_CTRL_TYPE_INTEGER64:
554 case V4L2_CTRL_TYPE_STRING:
555 /* Nope, these need v4l2_ext_control */
562 static void fill_event(struct v4l2_event *ev, struct v4l2_ctrl *ctrl, u32 changes)
564 memset(ev->reserved, 0, sizeof(ev->reserved));
565 ev->type = V4L2_EVENT_CTRL;
567 ev->u.ctrl.changes = changes;
568 ev->u.ctrl.type = ctrl->type;
569 ev->u.ctrl.flags = ctrl->flags;
570 if (ctrl->type == V4L2_CTRL_TYPE_STRING)
571 ev->u.ctrl.value64 = 0;
573 ev->u.ctrl.value64 = ctrl->cur.val64;
574 ev->u.ctrl.minimum = ctrl->minimum;
575 ev->u.ctrl.maximum = ctrl->maximum;
576 if (ctrl->type == V4L2_CTRL_TYPE_MENU)
579 ev->u.ctrl.step = ctrl->step;
580 ev->u.ctrl.default_value = ctrl->default_value;
583 static void send_event(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl, u32 changes)
585 struct v4l2_event ev;
586 struct v4l2_subscribed_event *sev;
588 if (list_empty(&ctrl->ev_subs))
590 fill_event(&ev, ctrl, changes);
592 list_for_each_entry(sev, &ctrl->ev_subs, node)
593 if (sev->fh && sev->fh != fh)
594 v4l2_event_queue_fh(sev->fh, &ev);
597 /* Helper function: copy the current control value back to the caller */
598 static int cur_to_user(struct v4l2_ext_control *c,
599 struct v4l2_ctrl *ctrl)
603 switch (ctrl->type) {
604 case V4L2_CTRL_TYPE_STRING:
605 len = strlen(ctrl->cur.string);
606 if (c->size < len + 1) {
610 return copy_to_user(c->string, ctrl->cur.string,
611 len + 1) ? -EFAULT : 0;
612 case V4L2_CTRL_TYPE_INTEGER64:
613 c->value64 = ctrl->cur.val64;
616 c->value = ctrl->cur.val;
622 /* Helper function: copy the caller-provider value as the new control value */
623 static int user_to_new(struct v4l2_ext_control *c,
624 struct v4l2_ctrl *ctrl)
630 switch (ctrl->type) {
631 case V4L2_CTRL_TYPE_INTEGER64:
632 ctrl->val64 = c->value64;
634 case V4L2_CTRL_TYPE_STRING:
638 if (size > ctrl->maximum + 1)
639 size = ctrl->maximum + 1;
640 ret = copy_from_user(ctrl->string, c->string, size);
642 char last = ctrl->string[size - 1];
644 ctrl->string[size - 1] = 0;
645 /* If the string was longer than ctrl->maximum,
646 then return an error. */
647 if (strlen(ctrl->string) == ctrl->maximum && last)
650 return ret ? -EFAULT : 0;
652 ctrl->val = c->value;
658 /* Helper function: copy the new control value back to the caller */
659 static int new_to_user(struct v4l2_ext_control *c,
660 struct v4l2_ctrl *ctrl)
664 switch (ctrl->type) {
665 case V4L2_CTRL_TYPE_STRING:
666 len = strlen(ctrl->string);
667 if (c->size < len + 1) {
668 c->size = ctrl->maximum + 1;
671 return copy_to_user(c->string, ctrl->string,
672 len + 1) ? -EFAULT : 0;
673 case V4L2_CTRL_TYPE_INTEGER64:
674 c->value64 = ctrl->val64;
677 c->value = ctrl->val;
683 /* Copy the new value to the current value. */
684 static void new_to_cur(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl,
685 bool update_inactive)
687 bool changed = false;
691 switch (ctrl->type) {
692 case V4L2_CTRL_TYPE_BUTTON:
695 case V4L2_CTRL_TYPE_STRING:
696 /* strings are always 0-terminated */
697 changed = strcmp(ctrl->string, ctrl->cur.string);
698 strcpy(ctrl->cur.string, ctrl->string);
700 case V4L2_CTRL_TYPE_INTEGER64:
701 changed = ctrl->val64 != ctrl->cur.val64;
702 ctrl->cur.val64 = ctrl->val64;
705 changed = ctrl->val != ctrl->cur.val;
706 ctrl->cur.val = ctrl->val;
709 if (update_inactive) {
710 ctrl->flags &= ~V4L2_CTRL_FLAG_INACTIVE;
711 if (!is_cur_manual(ctrl->cluster[0]))
712 ctrl->flags |= V4L2_CTRL_FLAG_INACTIVE;
714 if (changed || update_inactive)
716 (changed ? V4L2_EVENT_CTRL_CH_VALUE : 0) |
717 (update_inactive ? V4L2_EVENT_CTRL_CH_FLAGS : 0));
720 /* Copy the current value to the new value */
721 static void cur_to_new(struct v4l2_ctrl *ctrl)
725 switch (ctrl->type) {
726 case V4L2_CTRL_TYPE_STRING:
727 /* strings are always 0-terminated */
728 strcpy(ctrl->string, ctrl->cur.string);
730 case V4L2_CTRL_TYPE_INTEGER64:
731 ctrl->val64 = ctrl->cur.val64;
734 ctrl->val = ctrl->cur.val;
739 /* Return non-zero if one or more of the controls in the cluster has a new
740 value that differs from the current value. */
741 static int cluster_changed(struct v4l2_ctrl *master)
746 for (i = 0; !diff && i < master->ncontrols; i++) {
747 struct v4l2_ctrl *ctrl = master->cluster[i];
751 switch (ctrl->type) {
752 case V4L2_CTRL_TYPE_BUTTON:
753 /* Button controls are always 'different' */
755 case V4L2_CTRL_TYPE_STRING:
756 /* strings are always 0-terminated */
757 diff = strcmp(ctrl->string, ctrl->cur.string);
759 case V4L2_CTRL_TYPE_INTEGER64:
760 diff = ctrl->val64 != ctrl->cur.val64;
763 diff = ctrl->val != ctrl->cur.val;
770 /* Validate integer-type control */
771 static int validate_new_int(const struct v4l2_ctrl *ctrl, s32 *pval)
776 switch (ctrl->type) {
777 case V4L2_CTRL_TYPE_INTEGER:
778 /* Round towards the closest legal value */
779 val += ctrl->step / 2;
780 if (val < ctrl->minimum)
782 if (val > ctrl->maximum)
784 offset = val - ctrl->minimum;
785 offset = ctrl->step * (offset / ctrl->step);
786 val = ctrl->minimum + offset;
790 case V4L2_CTRL_TYPE_BOOLEAN:
794 case V4L2_CTRL_TYPE_MENU:
795 if (val < ctrl->minimum || val > ctrl->maximum)
797 if (ctrl->qmenu[val][0] == '\0' ||
798 (ctrl->menu_skip_mask & (1 << val)))
802 case V4L2_CTRL_TYPE_BUTTON:
803 case V4L2_CTRL_TYPE_CTRL_CLASS:
812 /* Validate a new control */
813 static int validate_new(const struct v4l2_ctrl *ctrl, struct v4l2_ext_control *c)
818 switch (ctrl->type) {
819 case V4L2_CTRL_TYPE_INTEGER:
820 case V4L2_CTRL_TYPE_BOOLEAN:
821 case V4L2_CTRL_TYPE_MENU:
822 case V4L2_CTRL_TYPE_BUTTON:
823 case V4L2_CTRL_TYPE_CTRL_CLASS:
824 return validate_new_int(ctrl, &c->value);
826 case V4L2_CTRL_TYPE_INTEGER64:
829 case V4L2_CTRL_TYPE_STRING:
831 if (len < ctrl->minimum)
833 if ((len - ctrl->minimum) % ctrl->step)
842 static inline u32 node2id(struct list_head *node)
844 return list_entry(node, struct v4l2_ctrl_ref, node)->ctrl->id;
847 /* Set the handler's error code if it wasn't set earlier already */
848 static inline int handler_set_err(struct v4l2_ctrl_handler *hdl, int err)
855 /* Initialize the handler */
856 int v4l2_ctrl_handler_init(struct v4l2_ctrl_handler *hdl,
857 unsigned nr_of_controls_hint)
859 mutex_init(&hdl->lock);
860 INIT_LIST_HEAD(&hdl->ctrls);
861 INIT_LIST_HEAD(&hdl->ctrl_refs);
862 hdl->nr_of_buckets = 1 + nr_of_controls_hint / 8;
863 hdl->buckets = kzalloc(sizeof(hdl->buckets[0]) * hdl->nr_of_buckets,
865 hdl->error = hdl->buckets ? 0 : -ENOMEM;
868 EXPORT_SYMBOL(v4l2_ctrl_handler_init);
870 /* Free all controls and control refs */
871 void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl)
873 struct v4l2_ctrl_ref *ref, *next_ref;
874 struct v4l2_ctrl *ctrl, *next_ctrl;
875 struct v4l2_subscribed_event *sev, *next_sev;
877 if (hdl == NULL || hdl->buckets == NULL)
880 mutex_lock(&hdl->lock);
882 list_for_each_entry_safe(ref, next_ref, &hdl->ctrl_refs, node) {
883 list_del(&ref->node);
886 /* Free all controls owned by the handler */
887 list_for_each_entry_safe(ctrl, next_ctrl, &hdl->ctrls, node) {
888 list_del(&ctrl->node);
889 list_for_each_entry_safe(sev, next_sev, &ctrl->ev_subs, node)
890 list_del(&sev->node);
897 mutex_unlock(&hdl->lock);
899 EXPORT_SYMBOL(v4l2_ctrl_handler_free);
901 /* For backwards compatibility: V4L2_CID_PRIVATE_BASE should no longer
902 be used except in G_CTRL, S_CTRL, QUERYCTRL and QUERYMENU when dealing
903 with applications that do not use the NEXT_CTRL flag.
905 We just find the n-th private user control. It's O(N), but that should not
906 be an issue in this particular case. */
907 static struct v4l2_ctrl_ref *find_private_ref(
908 struct v4l2_ctrl_handler *hdl, u32 id)
910 struct v4l2_ctrl_ref *ref;
912 id -= V4L2_CID_PRIVATE_BASE;
913 list_for_each_entry(ref, &hdl->ctrl_refs, node) {
914 /* Search for private user controls that are compatible with
916 if (V4L2_CTRL_ID2CLASS(ref->ctrl->id) == V4L2_CTRL_CLASS_USER &&
917 V4L2_CTRL_DRIVER_PRIV(ref->ctrl->id)) {
918 if (!type_is_int(ref->ctrl))
928 /* Find a control with the given ID. */
929 static struct v4l2_ctrl_ref *find_ref(struct v4l2_ctrl_handler *hdl, u32 id)
931 struct v4l2_ctrl_ref *ref;
934 id &= V4L2_CTRL_ID_MASK;
936 /* Old-style private controls need special handling */
937 if (id >= V4L2_CID_PRIVATE_BASE)
938 return find_private_ref(hdl, id);
939 bucket = id % hdl->nr_of_buckets;
941 /* Simple optimization: cache the last control found */
942 if (hdl->cached && hdl->cached->ctrl->id == id)
945 /* Not in cache, search the hash */
946 ref = hdl->buckets ? hdl->buckets[bucket] : NULL;
947 while (ref && ref->ctrl->id != id)
951 hdl->cached = ref; /* cache it! */
955 /* Find a control with the given ID. Take the handler's lock first. */
956 static struct v4l2_ctrl_ref *find_ref_lock(
957 struct v4l2_ctrl_handler *hdl, u32 id)
959 struct v4l2_ctrl_ref *ref = NULL;
962 mutex_lock(&hdl->lock);
963 ref = find_ref(hdl, id);
964 mutex_unlock(&hdl->lock);
969 /* Find a control with the given ID. */
970 struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id)
972 struct v4l2_ctrl_ref *ref = find_ref_lock(hdl, id);
974 return ref ? ref->ctrl : NULL;
976 EXPORT_SYMBOL(v4l2_ctrl_find);
978 /* Allocate a new v4l2_ctrl_ref and hook it into the handler. */
979 static int handler_new_ref(struct v4l2_ctrl_handler *hdl,
980 struct v4l2_ctrl *ctrl)
982 struct v4l2_ctrl_ref *ref;
983 struct v4l2_ctrl_ref *new_ref;
985 u32 class_ctrl = V4L2_CTRL_ID2CLASS(id) | 1;
986 int bucket = id % hdl->nr_of_buckets; /* which bucket to use */
988 /* Automatically add the control class if it is not yet present. */
989 if (id != class_ctrl && find_ref_lock(hdl, class_ctrl) == NULL)
990 if (!v4l2_ctrl_new_std(hdl, NULL, class_ctrl, 0, 0, 0, 0))
996 new_ref = kzalloc(sizeof(*new_ref), GFP_KERNEL);
998 return handler_set_err(hdl, -ENOMEM);
999 new_ref->ctrl = ctrl;
1000 if (ctrl->handler == hdl) {
1001 /* By default each control starts in a cluster of its own.
1002 new_ref->ctrl is basically a cluster array with one
1003 element, so that's perfect to use as the cluster pointer.
1004 But only do this for the handler that owns the control. */
1005 ctrl->cluster = &new_ref->ctrl;
1006 ctrl->ncontrols = 1;
1009 INIT_LIST_HEAD(&new_ref->node);
1011 mutex_lock(&hdl->lock);
1013 /* Add immediately at the end of the list if the list is empty, or if
1014 the last element in the list has a lower ID.
1015 This ensures that when elements are added in ascending order the
1016 insertion is an O(1) operation. */
1017 if (list_empty(&hdl->ctrl_refs) || id > node2id(hdl->ctrl_refs.prev)) {
1018 list_add_tail(&new_ref->node, &hdl->ctrl_refs);
1019 goto insert_in_hash;
1022 /* Find insert position in sorted list */
1023 list_for_each_entry(ref, &hdl->ctrl_refs, node) {
1024 if (ref->ctrl->id < id)
1026 /* Don't add duplicates */
1027 if (ref->ctrl->id == id) {
1031 list_add(&new_ref->node, ref->node.prev);
1036 /* Insert the control node in the hash */
1037 new_ref->next = hdl->buckets[bucket];
1038 hdl->buckets[bucket] = new_ref;
1041 mutex_unlock(&hdl->lock);
1045 /* Add a new control */
1046 static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl,
1047 const struct v4l2_ctrl_ops *ops,
1048 u32 id, const char *name, enum v4l2_ctrl_type type,
1049 s32 min, s32 max, u32 step, s32 def,
1050 u32 flags, const char * const *qmenu, void *priv)
1052 struct v4l2_ctrl *ctrl;
1053 unsigned sz_extra = 0;
1059 if (id == 0 || name == NULL || id >= V4L2_CID_PRIVATE_BASE ||
1061 (type == V4L2_CTRL_TYPE_INTEGER && step == 0) ||
1062 (type == V4L2_CTRL_TYPE_MENU && qmenu == NULL) ||
1063 (type == V4L2_CTRL_TYPE_STRING && max == 0)) {
1064 handler_set_err(hdl, -ERANGE);
1067 if ((type == V4L2_CTRL_TYPE_INTEGER ||
1068 type == V4L2_CTRL_TYPE_MENU ||
1069 type == V4L2_CTRL_TYPE_BOOLEAN) &&
1070 (def < min || def > max)) {
1071 handler_set_err(hdl, -ERANGE);
1075 if (type == V4L2_CTRL_TYPE_BUTTON)
1076 flags |= V4L2_CTRL_FLAG_WRITE_ONLY;
1077 else if (type == V4L2_CTRL_TYPE_CTRL_CLASS)
1078 flags |= V4L2_CTRL_FLAG_READ_ONLY;
1079 else if (type == V4L2_CTRL_TYPE_STRING)
1080 sz_extra += 2 * (max + 1);
1082 ctrl = kzalloc(sizeof(*ctrl) + sz_extra, GFP_KERNEL);
1084 handler_set_err(hdl, -ENOMEM);
1088 INIT_LIST_HEAD(&ctrl->node);
1089 INIT_LIST_HEAD(&ctrl->ev_subs);
1090 ctrl->handler = hdl;
1095 ctrl->flags = flags;
1096 ctrl->minimum = min;
1097 ctrl->maximum = max;
1099 ctrl->qmenu = qmenu;
1101 ctrl->cur.val = ctrl->val = ctrl->default_value = def;
1103 if (ctrl->type == V4L2_CTRL_TYPE_STRING) {
1104 ctrl->cur.string = (char *)&ctrl[1] + sz_extra - (max + 1);
1105 ctrl->string = (char *)&ctrl[1] + sz_extra - 2 * (max + 1);
1107 memset(ctrl->cur.string, ' ', ctrl->minimum);
1109 if (handler_new_ref(hdl, ctrl)) {
1113 mutex_lock(&hdl->lock);
1114 list_add_tail(&ctrl->node, &hdl->ctrls);
1115 mutex_unlock(&hdl->lock);
1119 struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl,
1120 const struct v4l2_ctrl_config *cfg, void *priv)
1123 struct v4l2_ctrl *ctrl;
1124 const char *name = cfg->name;
1125 const char * const *qmenu = cfg->qmenu;
1126 enum v4l2_ctrl_type type = cfg->type;
1127 u32 flags = cfg->flags;
1130 u32 step = cfg->step;
1134 v4l2_ctrl_fill(cfg->id, &name, &type, &min, &max, &step,
1137 is_menu = (cfg->type == V4L2_CTRL_TYPE_MENU);
1141 WARN_ON(cfg->menu_skip_mask);
1142 if (is_menu && qmenu == NULL)
1143 qmenu = v4l2_ctrl_get_menu(cfg->id);
1145 ctrl = v4l2_ctrl_new(hdl, cfg->ops, cfg->id, name,
1147 is_menu ? cfg->menu_skip_mask : step,
1148 def, flags, qmenu, priv);
1150 ctrl->is_private = cfg->is_private;
1151 ctrl->is_volatile = cfg->is_volatile;
1155 EXPORT_SYMBOL(v4l2_ctrl_new_custom);
1157 /* Helper function for standard non-menu controls */
1158 struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl,
1159 const struct v4l2_ctrl_ops *ops,
1160 u32 id, s32 min, s32 max, u32 step, s32 def)
1163 enum v4l2_ctrl_type type;
1166 v4l2_ctrl_fill(id, &name, &type, &min, &max, &step, &def, &flags);
1167 if (type == V4L2_CTRL_TYPE_MENU) {
1168 handler_set_err(hdl, -EINVAL);
1171 return v4l2_ctrl_new(hdl, ops, id, name, type,
1172 min, max, step, def, flags, NULL, NULL);
1174 EXPORT_SYMBOL(v4l2_ctrl_new_std);
1176 /* Helper function for standard menu controls */
1177 struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl,
1178 const struct v4l2_ctrl_ops *ops,
1179 u32 id, s32 max, s32 mask, s32 def)
1181 const char * const *qmenu = v4l2_ctrl_get_menu(id);
1183 enum v4l2_ctrl_type type;
1188 v4l2_ctrl_fill(id, &name, &type, &min, &max, &step, &def, &flags);
1189 if (type != V4L2_CTRL_TYPE_MENU) {
1190 handler_set_err(hdl, -EINVAL);
1193 return v4l2_ctrl_new(hdl, ops, id, name, type,
1194 0, max, mask, def, flags, qmenu, NULL);
1196 EXPORT_SYMBOL(v4l2_ctrl_new_std_menu);
1198 /* Add a control from another handler to this handler */
1199 struct v4l2_ctrl *v4l2_ctrl_add_ctrl(struct v4l2_ctrl_handler *hdl,
1200 struct v4l2_ctrl *ctrl)
1202 if (hdl == NULL || hdl->error)
1205 handler_set_err(hdl, -EINVAL);
1208 if (ctrl->handler == hdl)
1210 return handler_new_ref(hdl, ctrl) ? NULL : ctrl;
1212 EXPORT_SYMBOL(v4l2_ctrl_add_ctrl);
1214 /* Add the controls from another handler to our own. */
1215 int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
1216 struct v4l2_ctrl_handler *add)
1218 struct v4l2_ctrl *ctrl;
1221 /* Do nothing if either handler is NULL or if they are the same */
1222 if (!hdl || !add || hdl == add)
1226 mutex_lock(&add->lock);
1227 list_for_each_entry(ctrl, &add->ctrls, node) {
1228 /* Skip handler-private controls. */
1229 if (ctrl->is_private)
1231 /* And control classes */
1232 if (ctrl->type == V4L2_CTRL_TYPE_CTRL_CLASS)
1234 ret = handler_new_ref(hdl, ctrl);
1238 mutex_unlock(&add->lock);
1241 EXPORT_SYMBOL(v4l2_ctrl_add_handler);
1243 /* Cluster controls */
1244 void v4l2_ctrl_cluster(unsigned ncontrols, struct v4l2_ctrl **controls)
1248 /* The first control is the master control and it must not be NULL */
1249 BUG_ON(ncontrols == 0 || controls[0] == NULL);
1251 for (i = 0; i < ncontrols; i++) {
1253 controls[i]->cluster = controls;
1254 controls[i]->ncontrols = ncontrols;
1258 EXPORT_SYMBOL(v4l2_ctrl_cluster);
1260 void v4l2_ctrl_auto_cluster(unsigned ncontrols, struct v4l2_ctrl **controls,
1261 u8 manual_val, bool set_volatile)
1263 struct v4l2_ctrl *master = controls[0];
1267 v4l2_ctrl_cluster(ncontrols, controls);
1268 WARN_ON(ncontrols <= 1);
1269 WARN_ON(manual_val < master->minimum || manual_val > master->maximum);
1270 master->is_auto = true;
1271 master->manual_mode_value = manual_val;
1272 master->flags |= V4L2_CTRL_FLAG_UPDATE;
1273 flag = is_cur_manual(master) ? 0 : V4L2_CTRL_FLAG_INACTIVE;
1275 for (i = 1; i < ncontrols; i++)
1277 controls[i]->is_volatile = set_volatile;
1278 controls[i]->flags |= flag;
1281 EXPORT_SYMBOL(v4l2_ctrl_auto_cluster);
1283 /* Activate/deactivate a control. */
1284 void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active)
1286 /* invert since the actual flag is called 'inactive' */
1287 bool inactive = !active;
1294 /* set V4L2_CTRL_FLAG_INACTIVE */
1295 old = test_and_set_bit(4, &ctrl->flags);
1297 /* clear V4L2_CTRL_FLAG_INACTIVE */
1298 old = test_and_clear_bit(4, &ctrl->flags);
1299 if (old != inactive)
1300 send_event(NULL, ctrl, V4L2_EVENT_CTRL_CH_FLAGS);
1302 EXPORT_SYMBOL(v4l2_ctrl_activate);
1304 /* Grab/ungrab a control.
1305 Typically used when streaming starts and you want to grab controls,
1306 preventing the user from changing them.
1308 Just call this and the framework will block any attempts to change
1310 void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed)
1317 v4l2_ctrl_lock(ctrl);
1319 /* set V4L2_CTRL_FLAG_GRABBED */
1320 old = test_and_set_bit(1, &ctrl->flags);
1322 /* clear V4L2_CTRL_FLAG_GRABBED */
1323 old = test_and_clear_bit(1, &ctrl->flags);
1325 send_event(NULL, ctrl, V4L2_EVENT_CTRL_CH_FLAGS);
1326 v4l2_ctrl_unlock(ctrl);
1328 EXPORT_SYMBOL(v4l2_ctrl_grab);
1330 /* Log the control name and value */
1331 static void log_ctrl(const struct v4l2_ctrl *ctrl,
1332 const char *prefix, const char *colon)
1334 int fl_inact = ctrl->flags & V4L2_CTRL_FLAG_INACTIVE;
1335 int fl_grabbed = ctrl->flags & V4L2_CTRL_FLAG_GRABBED;
1337 if (ctrl->flags & (V4L2_CTRL_FLAG_DISABLED | V4L2_CTRL_FLAG_WRITE_ONLY))
1339 if (ctrl->type == V4L2_CTRL_TYPE_CTRL_CLASS)
1342 printk(KERN_INFO "%s%s%s: ", prefix, colon, ctrl->name);
1344 switch (ctrl->type) {
1345 case V4L2_CTRL_TYPE_INTEGER:
1346 printk(KERN_CONT "%d", ctrl->cur.val);
1348 case V4L2_CTRL_TYPE_BOOLEAN:
1349 printk(KERN_CONT "%s", ctrl->cur.val ? "true" : "false");
1351 case V4L2_CTRL_TYPE_MENU:
1352 printk(KERN_CONT "%s", ctrl->qmenu[ctrl->cur.val]);
1354 case V4L2_CTRL_TYPE_INTEGER64:
1355 printk(KERN_CONT "%lld", ctrl->cur.val64);
1357 case V4L2_CTRL_TYPE_STRING:
1358 printk(KERN_CONT "%s", ctrl->cur.string);
1361 printk(KERN_CONT "unknown type %d", ctrl->type);
1364 if (fl_inact && fl_grabbed)
1365 printk(KERN_CONT " (inactive, grabbed)\n");
1367 printk(KERN_CONT " (inactive)\n");
1368 else if (fl_grabbed)
1369 printk(KERN_CONT " (grabbed)\n");
1371 printk(KERN_CONT "\n");
1374 /* Log all controls owned by the handler */
1375 void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl,
1378 struct v4l2_ctrl *ctrl;
1379 const char *colon = "";
1386 len = strlen(prefix);
1387 if (len && prefix[len - 1] != ' ')
1389 mutex_lock(&hdl->lock);
1390 list_for_each_entry(ctrl, &hdl->ctrls, node)
1391 if (!(ctrl->flags & V4L2_CTRL_FLAG_DISABLED))
1392 log_ctrl(ctrl, prefix, colon);
1393 mutex_unlock(&hdl->lock);
1395 EXPORT_SYMBOL(v4l2_ctrl_handler_log_status);
1397 /* Call s_ctrl for all controls owned by the handler */
1398 int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl)
1400 struct v4l2_ctrl *ctrl;
1405 mutex_lock(&hdl->lock);
1406 list_for_each_entry(ctrl, &hdl->ctrls, node)
1409 list_for_each_entry(ctrl, &hdl->ctrls, node) {
1410 struct v4l2_ctrl *master = ctrl->cluster[0];
1413 /* Skip if this control was already handled by a cluster. */
1417 for (i = 0; i < master->ncontrols; i++) {
1418 if (master->cluster[i]) {
1419 cur_to_new(master->cluster[i]);
1420 master->cluster[i]->is_new = 1;
1424 /* Skip button controls and read-only controls. */
1425 if (ctrl->type == V4L2_CTRL_TYPE_BUTTON ||
1426 (ctrl->flags & V4L2_CTRL_FLAG_READ_ONLY))
1428 ret = call_op(master, s_ctrl);
1431 for (i = 0; i < master->ncontrols; i++)
1432 if (master->cluster[i])
1433 master->cluster[i]->done = true;
1435 mutex_unlock(&hdl->lock);
1438 EXPORT_SYMBOL(v4l2_ctrl_handler_setup);
1440 /* Implement VIDIOC_QUERYCTRL */
1441 int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc)
1443 u32 id = qc->id & V4L2_CTRL_ID_MASK;
1444 struct v4l2_ctrl_ref *ref;
1445 struct v4l2_ctrl *ctrl;
1450 mutex_lock(&hdl->lock);
1452 /* Try to find it */
1453 ref = find_ref(hdl, id);
1455 if ((qc->id & V4L2_CTRL_FLAG_NEXT_CTRL) && !list_empty(&hdl->ctrl_refs)) {
1456 /* Find the next control with ID > qc->id */
1458 /* Did we reach the end of the control list? */
1459 if (id >= node2id(hdl->ctrl_refs.prev)) {
1460 ref = NULL; /* Yes, so there is no next control */
1462 /* We found a control with the given ID, so just get
1463 the next one in the list. */
1464 ref = list_entry(ref->node.next, typeof(*ref), node);
1466 /* No control with the given ID exists, so start
1467 searching for the next largest ID. We know there
1468 is one, otherwise the first 'if' above would have
1470 list_for_each_entry(ref, &hdl->ctrl_refs, node)
1471 if (id < ref->ctrl->id)
1475 mutex_unlock(&hdl->lock);
1480 memset(qc, 0, sizeof(*qc));
1481 if (id >= V4L2_CID_PRIVATE_BASE)
1485 strlcpy(qc->name, ctrl->name, sizeof(qc->name));
1486 qc->minimum = ctrl->minimum;
1487 qc->maximum = ctrl->maximum;
1488 qc->default_value = ctrl->default_value;
1489 if (ctrl->type == V4L2_CTRL_TYPE_MENU)
1492 qc->step = ctrl->step;
1493 qc->flags = ctrl->flags;
1494 qc->type = ctrl->type;
1497 EXPORT_SYMBOL(v4l2_queryctrl);
1499 int v4l2_subdev_queryctrl(struct v4l2_subdev *sd, struct v4l2_queryctrl *qc)
1501 if (qc->id & V4L2_CTRL_FLAG_NEXT_CTRL)
1503 return v4l2_queryctrl(sd->ctrl_handler, qc);
1505 EXPORT_SYMBOL(v4l2_subdev_queryctrl);
1507 /* Implement VIDIOC_QUERYMENU */
1508 int v4l2_querymenu(struct v4l2_ctrl_handler *hdl, struct v4l2_querymenu *qm)
1510 struct v4l2_ctrl *ctrl;
1513 ctrl = v4l2_ctrl_find(hdl, qm->id);
1519 if (ctrl->qmenu == NULL ||
1520 i < ctrl->minimum || i > ctrl->maximum)
1522 /* Use mask to see if this menu item should be skipped */
1523 if (ctrl->menu_skip_mask & (1 << i))
1525 /* Empty menu items should also be skipped */
1526 if (ctrl->qmenu[i] == NULL || ctrl->qmenu[i][0] == '\0')
1528 strlcpy(qm->name, ctrl->qmenu[i], sizeof(qm->name));
1531 EXPORT_SYMBOL(v4l2_querymenu);
1533 int v4l2_subdev_querymenu(struct v4l2_subdev *sd, struct v4l2_querymenu *qm)
1535 return v4l2_querymenu(sd->ctrl_handler, qm);
1537 EXPORT_SYMBOL(v4l2_subdev_querymenu);
1541 /* Some general notes on the atomic requirements of VIDIOC_G/TRY/S_EXT_CTRLS:
1543 It is not a fully atomic operation, just best-effort only. After all, if
1544 multiple controls have to be set through multiple i2c writes (for example)
1545 then some initial writes may succeed while others fail. Thus leaving the
1546 system in an inconsistent state. The question is how much effort you are
1547 willing to spend on trying to make something atomic that really isn't.
1549 From the point of view of an application the main requirement is that
1550 when you call VIDIOC_S_EXT_CTRLS and some values are invalid then an
1551 error should be returned without actually affecting any controls.
1553 If all the values are correct, then it is acceptable to just give up
1554 in case of low-level errors.
1556 It is important though that the application can tell when only a partial
1557 configuration was done. The way we do that is through the error_idx field
1558 of struct v4l2_ext_controls: if that is equal to the count field then no
1559 controls were affected. Otherwise all controls before that index were
1560 successful in performing their 'get' or 'set' operation, the control at
1561 the given index failed, and you don't know what happened with the controls
1562 after the failed one. Since if they were part of a control cluster they
1563 could have been successfully processed (if a cluster member was encountered
1564 at index < error_idx), they could have failed (if a cluster member was at
1565 error_idx), or they may not have been processed yet (if the first cluster
1566 member appeared after error_idx).
1568 It is all fairly theoretical, though. In practice all you can do is to
1569 bail out. If error_idx == count, then it is an application bug. If
1570 error_idx < count then it is only an application bug if the error code was
1571 EBUSY. That usually means that something started streaming just when you
1572 tried to set the controls. In all other cases it is a driver/hardware
1573 problem and all you can do is to retry or bail out.
1575 Note that these rules do not apply to VIDIOC_TRY_EXT_CTRLS: since that
1576 never modifies controls the error_idx is just set to whatever control
1577 has an invalid value.
1580 /* Prepare for the extended g/s/try functions.
1581 Find the controls in the control array and do some basic checks. */
1582 static int prepare_ext_ctrls(struct v4l2_ctrl_handler *hdl,
1583 struct v4l2_ext_controls *cs,
1584 struct v4l2_ctrl_helper *helpers)
1586 struct v4l2_ctrl_helper *h;
1587 bool have_clusters = false;
1590 for (i = 0, h = helpers; i < cs->count; i++, h++) {
1591 struct v4l2_ext_control *c = &cs->controls[i];
1592 struct v4l2_ctrl_ref *ref;
1593 struct v4l2_ctrl *ctrl;
1594 u32 id = c->id & V4L2_CTRL_ID_MASK;
1598 if (cs->ctrl_class && V4L2_CTRL_ID2CLASS(id) != cs->ctrl_class)
1601 /* Old-style private controls are not allowed for
1602 extended controls */
1603 if (id >= V4L2_CID_PRIVATE_BASE)
1605 ref = find_ref_lock(hdl, id);
1609 if (ctrl->flags & V4L2_CTRL_FLAG_DISABLED)
1612 if (ctrl->cluster[0]->ncontrols > 1)
1613 have_clusters = true;
1614 if (ctrl->cluster[0] != ctrl)
1615 ref = find_ref_lock(hdl, ctrl->cluster[0]->id);
1616 /* Store the ref to the master control of the cluster */
1619 /* Initially set next to 0, meaning that there is no other
1620 control in this helper array belonging to the same
1625 /* We are done if there were no controls that belong to a multi-
1630 /* The code below figures out in O(n) time which controls in the list
1631 belong to the same cluster. */
1633 /* This has to be done with the handler lock taken. */
1634 mutex_lock(&hdl->lock);
1636 /* First zero the helper field in the master control references */
1637 for (i = 0; i < cs->count; i++)
1638 helpers[i].mref->helper = 0;
1639 for (i = 0, h = helpers; i < cs->count; i++, h++) {
1640 struct v4l2_ctrl_ref *mref = h->mref;
1642 /* If the mref->helper is set, then it points to an earlier
1643 helper that belongs to the same cluster. */
1645 /* Set the next field of mref->helper to the current
1646 index: this means that that earlier helper now
1647 points to the next helper in the same cluster. */
1648 mref->helper->next = i;
1649 /* mref should be set only for the first helper in the
1650 cluster, clear the others. */
1653 /* Point the mref helper to the current helper struct. */
1656 mutex_unlock(&hdl->lock);
1660 /* Handles the corner case where cs->count == 0. It checks whether the
1661 specified control class exists. If that class ID is 0, then it checks
1662 whether there are any controls at all. */
1663 static int class_check(struct v4l2_ctrl_handler *hdl, u32 ctrl_class)
1665 if (ctrl_class == 0)
1666 return list_empty(&hdl->ctrl_refs) ? -EINVAL : 0;
1667 return find_ref_lock(hdl, ctrl_class | 1) ? 0 : -EINVAL;
1672 /* Get extended controls. Allocates the helpers array if needed. */
1673 int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *cs)
1675 struct v4l2_ctrl_helper helper[4];
1676 struct v4l2_ctrl_helper *helpers = helper;
1680 cs->error_idx = cs->count;
1681 cs->ctrl_class = V4L2_CTRL_ID2CLASS(cs->ctrl_class);
1687 return class_check(hdl, cs->ctrl_class);
1689 if (cs->count > ARRAY_SIZE(helper)) {
1690 helpers = kmalloc(sizeof(helper[0]) * cs->count, GFP_KERNEL);
1691 if (helpers == NULL)
1695 ret = prepare_ext_ctrls(hdl, cs, helpers);
1696 cs->error_idx = cs->count;
1698 for (i = 0; !ret && i < cs->count; i++)
1699 if (helpers[i].ctrl->flags & V4L2_CTRL_FLAG_WRITE_ONLY)
1702 for (i = 0; !ret && i < cs->count; i++) {
1703 int (*ctrl_to_user)(struct v4l2_ext_control *c,
1704 struct v4l2_ctrl *ctrl) = cur_to_user;
1705 struct v4l2_ctrl *master;
1707 if (helpers[i].mref == NULL)
1710 master = helpers[i].mref->ctrl;
1713 v4l2_ctrl_lock(master);
1715 /* g_volatile_ctrl will update the new control values */
1716 if (has_op(master, g_volatile_ctrl) && !is_cur_manual(master)) {
1717 for (j = 0; j < master->ncontrols; j++)
1718 cur_to_new(master->cluster[j]);
1719 ret = call_op(master, g_volatile_ctrl);
1720 ctrl_to_user = new_to_user;
1722 /* If OK, then copy the current (for non-volatile controls)
1723 or the new (for volatile controls) control values to the
1729 ret = ctrl_to_user(cs->controls + idx,
1731 idx = helpers[idx].next;
1732 } while (!ret && idx);
1734 v4l2_ctrl_unlock(master);
1737 if (cs->count > ARRAY_SIZE(helper))
1741 EXPORT_SYMBOL(v4l2_g_ext_ctrls);
1743 int v4l2_subdev_g_ext_ctrls(struct v4l2_subdev *sd, struct v4l2_ext_controls *cs)
1745 return v4l2_g_ext_ctrls(sd->ctrl_handler, cs);
1747 EXPORT_SYMBOL(v4l2_subdev_g_ext_ctrls);
1749 /* Helper function to get a single control */
1750 static int get_ctrl(struct v4l2_ctrl *ctrl, s32 *val)
1752 struct v4l2_ctrl *master = ctrl->cluster[0];
1756 if (ctrl->flags & V4L2_CTRL_FLAG_WRITE_ONLY)
1759 v4l2_ctrl_lock(master);
1760 /* g_volatile_ctrl will update the current control values */
1761 if (ctrl->is_volatile && !is_cur_manual(master)) {
1762 for (i = 0; i < master->ncontrols; i++)
1763 cur_to_new(master->cluster[i]);
1764 ret = call_op(master, g_volatile_ctrl);
1767 *val = ctrl->cur.val;
1769 v4l2_ctrl_unlock(master);
1773 int v4l2_g_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_control *control)
1775 struct v4l2_ctrl *ctrl = v4l2_ctrl_find(hdl, control->id);
1777 if (ctrl == NULL || !type_is_int(ctrl))
1779 return get_ctrl(ctrl, &control->value);
1781 EXPORT_SYMBOL(v4l2_g_ctrl);
1783 int v4l2_subdev_g_ctrl(struct v4l2_subdev *sd, struct v4l2_control *control)
1785 return v4l2_g_ctrl(sd->ctrl_handler, control);
1787 EXPORT_SYMBOL(v4l2_subdev_g_ctrl);
1789 s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl)
1793 /* It's a driver bug if this happens. */
1794 WARN_ON(!type_is_int(ctrl));
1795 get_ctrl(ctrl, &val);
1798 EXPORT_SYMBOL(v4l2_ctrl_g_ctrl);
1801 /* Core function that calls try/s_ctrl and ensures that the new value is
1802 copied to the current value on a set.
1803 Must be called with ctrl->handler->lock held. */
1804 static int try_or_set_cluster(struct v4l2_fh *fh,
1805 struct v4l2_ctrl *master, bool set)
1811 /* Go through the cluster and either validate the new value or
1812 (if no new value was set), copy the current value to the new
1813 value, ensuring a consistent view for the control ops when
1815 for (i = 0; i < master->ncontrols; i++) {
1816 struct v4l2_ctrl *ctrl = master->cluster[i];
1821 if (!ctrl->is_new) {
1825 /* Check again: it may have changed since the
1826 previous check in try_or_set_ext_ctrls(). */
1827 if (set && (ctrl->flags & V4L2_CTRL_FLAG_GRABBED))
1831 ret = call_op(master, try_ctrl);
1833 /* Don't set if there is no change */
1834 if (ret || !set || !cluster_changed(master))
1836 ret = call_op(master, s_ctrl);
1840 /* If OK, then make the new values permanent. */
1841 update_flag = is_cur_manual(master) != is_new_manual(master);
1842 for (i = 0; i < master->ncontrols; i++)
1843 new_to_cur(fh, master->cluster[i], update_flag && i > 0);
1847 /* Validate controls. */
1848 static int validate_ctrls(struct v4l2_ext_controls *cs,
1849 struct v4l2_ctrl_helper *helpers, bool set)
1854 cs->error_idx = cs->count;
1855 for (i = 0; i < cs->count; i++) {
1856 struct v4l2_ctrl *ctrl = helpers[i].ctrl;
1860 if (ctrl->flags & V4L2_CTRL_FLAG_READ_ONLY)
1862 /* This test is also done in try_set_control_cluster() which
1863 is called in atomic context, so that has the final say,
1864 but it makes sense to do an up-front check as well. Once
1865 an error occurs in try_set_control_cluster() some other
1866 controls may have been set already and we want to do a
1867 best-effort to avoid that. */
1868 if (set && (ctrl->flags & V4L2_CTRL_FLAG_GRABBED))
1870 ret = validate_new(ctrl, &cs->controls[i]);
1877 /* Try or try-and-set controls */
1878 static int try_set_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1879 struct v4l2_ext_controls *cs,
1882 struct v4l2_ctrl_helper helper[4];
1883 struct v4l2_ctrl_helper *helpers = helper;
1887 cs->error_idx = cs->count;
1888 cs->ctrl_class = V4L2_CTRL_ID2CLASS(cs->ctrl_class);
1894 return class_check(hdl, cs->ctrl_class);
1896 if (cs->count > ARRAY_SIZE(helper)) {
1897 helpers = kmalloc(sizeof(helper[0]) * cs->count, GFP_KERNEL);
1901 ret = prepare_ext_ctrls(hdl, cs, helpers);
1903 ret = validate_ctrls(cs, helpers, set);
1905 cs->error_idx = cs->count;
1906 for (i = 0; !ret && i < cs->count; i++) {
1907 struct v4l2_ctrl *master;
1910 if (helpers[i].mref == NULL)
1914 master = helpers[i].mref->ctrl;
1915 v4l2_ctrl_lock(master);
1917 /* Reset the 'is_new' flags of the cluster */
1918 for (j = 0; j < master->ncontrols; j++)
1919 if (master->cluster[j])
1920 master->cluster[j]->is_new = 0;
1922 /* Copy the new caller-supplied control values.
1923 user_to_new() sets 'is_new' to 1. */
1925 ret = user_to_new(cs->controls + idx, helpers[idx].ctrl);
1926 idx = helpers[idx].next;
1927 } while (!ret && idx);
1930 ret = try_or_set_cluster(fh, master, set);
1932 /* Copy the new values back to userspace. */
1936 ret = user_to_new(cs->controls + idx,
1938 idx = helpers[idx].next;
1939 } while (!ret && idx);
1941 v4l2_ctrl_unlock(master);
1944 if (cs->count > ARRAY_SIZE(helper))
1949 int v4l2_try_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *cs)
1951 return try_set_ext_ctrls(NULL, hdl, cs, false);
1953 EXPORT_SYMBOL(v4l2_try_ext_ctrls);
1955 int v4l2_s_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
1956 struct v4l2_ext_controls *cs)
1958 return try_set_ext_ctrls(fh, hdl, cs, true);
1960 EXPORT_SYMBOL(v4l2_s_ext_ctrls);
1962 int v4l2_subdev_try_ext_ctrls(struct v4l2_subdev *sd, struct v4l2_ext_controls *cs)
1964 return try_set_ext_ctrls(NULL, sd->ctrl_handler, cs, false);
1966 EXPORT_SYMBOL(v4l2_subdev_try_ext_ctrls);
1968 int v4l2_subdev_s_ext_ctrls(struct v4l2_subdev *sd, struct v4l2_ext_controls *cs)
1970 return try_set_ext_ctrls(NULL, sd->ctrl_handler, cs, true);
1972 EXPORT_SYMBOL(v4l2_subdev_s_ext_ctrls);
1974 /* Helper function for VIDIOC_S_CTRL compatibility */
1975 static int set_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl, s32 *val)
1977 struct v4l2_ctrl *master = ctrl->cluster[0];
1981 ret = validate_new_int(ctrl, val);
1985 v4l2_ctrl_lock(ctrl);
1987 /* Reset the 'is_new' flags of the cluster */
1988 for (i = 0; i < master->ncontrols; i++)
1989 if (master->cluster[i])
1990 master->cluster[i]->is_new = 0;
1994 ret = try_or_set_cluster(fh, master, true);
1995 *val = ctrl->cur.val;
1996 v4l2_ctrl_unlock(ctrl);
2000 int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
2001 struct v4l2_control *control)
2003 struct v4l2_ctrl *ctrl = v4l2_ctrl_find(hdl, control->id);
2005 if (ctrl == NULL || !type_is_int(ctrl))
2008 if (ctrl->flags & V4L2_CTRL_FLAG_READ_ONLY)
2011 return set_ctrl(fh, ctrl, &control->value);
2013 EXPORT_SYMBOL(v4l2_s_ctrl);
2015 int v4l2_subdev_s_ctrl(struct v4l2_subdev *sd, struct v4l2_control *control)
2017 return v4l2_s_ctrl(NULL, sd->ctrl_handler, control);
2019 EXPORT_SYMBOL(v4l2_subdev_s_ctrl);
2021 int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val)
2023 /* It's a driver bug if this happens. */
2024 WARN_ON(!type_is_int(ctrl));
2025 return set_ctrl(NULL, ctrl, &val);
2027 EXPORT_SYMBOL(v4l2_ctrl_s_ctrl);
2029 void v4l2_ctrl_add_event(struct v4l2_ctrl *ctrl,
2030 struct v4l2_subscribed_event *sev)
2032 v4l2_ctrl_lock(ctrl);
2033 list_add_tail(&sev->node, &ctrl->ev_subs);
2034 if (ctrl->type != V4L2_CTRL_TYPE_CTRL_CLASS &&
2035 (sev->flags & V4L2_EVENT_SUB_FL_SEND_INITIAL)) {
2036 struct v4l2_event ev;
2037 u32 changes = V4L2_EVENT_CTRL_CH_FLAGS;
2039 if (!(ctrl->flags & V4L2_CTRL_FLAG_WRITE_ONLY))
2040 changes |= V4L2_EVENT_CTRL_CH_VALUE;
2041 fill_event(&ev, ctrl, changes);
2042 v4l2_event_queue_fh(sev->fh, &ev);
2044 v4l2_ctrl_unlock(ctrl);
2046 EXPORT_SYMBOL(v4l2_ctrl_add_event);
2048 void v4l2_ctrl_del_event(struct v4l2_ctrl *ctrl,
2049 struct v4l2_subscribed_event *sev)
2051 v4l2_ctrl_lock(ctrl);
2052 list_del(&sev->node);
2053 v4l2_ctrl_unlock(ctrl);
2055 EXPORT_SYMBOL(v4l2_ctrl_del_event);